Cotter pin spreader



Patented Nov. 25, 1947 CUTTER PIN SPREADER Sven J. Strd, Chicago, Ill.,assignor.- to T.V & S,V Corporation, Chicago.. Ill... a corporation.ot..

Illinois Application December 22, 1945;.Seriail No. 636,837.

6 Claims. l;

My invention relates to cotter pins, withspecial reference tocotter pinassemblies constructed for self-spreading.A action, and is directedspecificallytoimprovements in the spreader member employed Vin suchassemblies.

In a cotter pin of thepresent type the assembly comprisesaecotter-pin-member or cotter pin proper, hayngthe usual two arms incombination with a spreader member extending between the two arms.Duringshipment and handling of the assembly prior to use,y the-Cotterpin member'and the wedge member are inlretracted positions relative toeachother. When; the cotter; pinis ulti,- mately driven into .place -forservice as a retaining means, the spreader member is immobilized atacertain pointso that the-subsequent: relative longitudinal movement ofthe Cotter pin member causes the arms of the cotter pin membertol bewedged apart at theirinner ends by the spreader member.

TheA generalconstruction of such a spreader' memberina-cotter=pin-assembly as taught by the prior artis to betoundin theTaylor Patent No. 1,768,721, andv theA Strid Patents Nos. 2,153,440,2,166,614, 2,373,983, and 2,490,960.; Such a spreader member isfabricated by steps including cutting a blank of suitable-congurationout of sheet metal andY bending.; the blank to form two side flanges..ci tapering configuration to serve-as wedge means-in the spreading ofthe cotter pin.

Iny all of these-prior disclosures the configuration of the. blank.lrelativeto the lines along which the metalis bent to'formv the flangesis suchas to oppose the bending action unduly, and is such as toresult.in. distortion and weakening of the material adjacentv the-inner ends-ofthe flanges. In consequence'theblankis Yso diicult to form thattheforming cost is relatively high.. Often the metal yieldsto theforming forces unevenlyso that one sideiiangeishigher than the other.Close .inspection is required and not all of the re.- jectedpiecescan besalvaged by further process-- ing.

The object.. of the present invention is tonnaprovee the constructionyand the-.method of construction. of .sucha spreader member by eliminateing. undue.; resistanceY to tbey bending of theyspreaderflanges:andbyavoiding weakeningof the. material by strainanddistortion.. 1n general, ,thisl object is. attained by changing theinitialv conb guration ofthe spreader blank to a congnration permitting.both ends-of the bend lines `for the side flanges to extend to theedges of the blank. When.

the bend. lines.. arethusk arranged to, extend. from edge. to.l edge.of; the. blank. the metal may be bent.

2` inz a clean-cut manner in a single formingfonerationwithoutadverselyaffecting the metal of the. blanlradjacent to the inner ends of the bendlines. The` new procedure in construction saves labor, lightens the.burden of inspection, and

greatly reduces the number of rejections. l have discovered' that acertain pinching. action in the older. practicerwas the cause of theuneven form ing of the side anges, andi now avoid such. pinching action.

The above andotherv objects and advantages :of my invention will beapparent in the following detailed description taken with theaccompanying drawings.

Inthe drawingawhich are to be regarded as merely illustrative;

Fig; 1 is a side elevation of a typical cotter pin assemblyincluding myimproved spreader mem--l ber;

Fig. 2 is afragmentary planviewon an enlarged scale of a-spreader blankaccording/to one practice of ,my invention.;

Fig, 3 is a fragmentary. plan view of the spreader fabricated from theblank oi.4 Fig. 2;

Fig. 4 isa fragmentary side elevation ofk the nished spreader;

Fig,v 5 is atransverse section :taken as indicated by the 1ine755 lofFig. 4;

Figs. 6, '7 and 8 are views corresponding to Figs. 2, 3 and 4, butshowing the preferred. practice of my invention;

Fig. 9 is-a fragmentary plan View similar to Eig. 7eXemp1ifying. athirdpractice of my invention; and

Figs. 10, l1 and 142 are-views correspondingl to Figs. 6, .7 and 8,indicating-.how such a spreader member has been vfabricated heretofore.

In the-Cotter: pin assembly shown in Fig, 1, the Cotter pin. member,generally designated 2G, is. formed from a. single piece of suitablehalf round stock, and comprises the usual twoarms 2l interconnected byaloopZZ, theA arms being sprung together. Inserted between the. arms 2|is a spreader. member 23.y having. two side flanges 25 atene endlofytheusllal tapered conguration to serve aslwedgeimeans for. spreading thearms .21.

At .tbe innerY end oftbe spreader. member 23 is a pair of laterallyextending wings/28 to serve two-purposes- One of the purposes is toVprovide an.v enlargement. to limit.. the movement. ofthe spreadermember. inton abore Vwhen the Cotter pin assembly isbeinginstalled,thereby to hold the spreader member` stationary during the nal movement`oi thecotter pinmember into Ithe bore; v'Ibostbe relative movementbetween the spreader;

member and the cotter pin member is provided as required for thespreading action. The second purpose of the two wings 26 is to limitlateral movement of the spreader member relative to the cotter pinmember prior to installation of the device, and for this purpose the twowings are sufliciently bent to engage the opposite sides of the Cotterpin member 2U.

The particular spreader member 23 shown in Fig. 1 is also provided withsmall tabs or flanges 21 on its opposite side that fit snugly againstthe cotter pin member 20 to prevent lateral movement between thespreader member and the cotter pin member at a second point. Otherexpedients may be employed to serve the purpose of the tabs 2l, as shownin the Strid Patents Nos. 2,166,614 and 2,400,960. None of theseexpedients conflict with the improvement disclosed herein.

The present invention is primarily concerned with the construction ofthe side anges 25 that provide the wedging action for spreading thecotter pin member 20. In all five of the prior disclosures mentionedabove the leading end of the spreader member, including the wedging sideflanges 2'5, is formed in the manner indicated by Figs. 10, 11 and 12.

Fig. shows a flat sheet metal blank having a body portion 28 withparallel side edges 33 and having an enlargement 3l at one end withdiverging side edges 32. It is to be noted that the inner ends of thediverging side edges 32 meet the parallel side edges 30.

Since the width of the body portion 28 of the usual blank isapproximately the diameter of the cotter pin assembly, and thereforeclose to the diameter of the bore into which the cotter pin is to beinstalled, it is obvious that the overall width of the finished spreadermember across the two wedging side flanges must be appreciably less thanthe width of the body portion 28. Otherwise the upstanding side angeswould not lie entirely within the circle defined by the bore and wouldprevent the leading end of the spreader member from entering the bore.It is apparent, then, that to form the finished spreader member from theblank shown in Fig. 10 it is necessary not only to bend the metal of theblank 90 to form the two wedging side flanges, but also to pinch themetal.

The necessity for pinching action is apparent from the position of thedotted lines 23 in Fig. l0, representing the lines on which the metal isbent to form the side flanges. Note that these lines terminate at theirinner ends inward from the side edges of the blank.

Fig. 11 indicates how the metal is pinched to form the two wedging sideflanges 33, the pinching action being concentrated in the regionsdesignated 34 adjacent the inner ends of the side flanges. In practicethe wedging side flanges 33 of Fig. l1 are best formed in two steps, andoften additional hand work is required to permit the finished pieces topass inspection. Even with two forming steps the metal is distorted ormutilated at the regions 34 to such a degree that the metal across thespreader member between the two regions 34 tends to be weakened eitherby crystallization or by the formation of small ssures. It is to beborne in mind that the wedging action for spreading the ends of thecotter pin member involves high longitudinal stress in tension at thisparticular part of the spreader member.

In one practice of the present invention illustrated by Figs. 2 to 4, Iemploy a sheet metal blank, generally designated 35, having the usualbody portion 28 and end enlargement 3 l, the body portion havingparallel side edges 30 and the enlargement having the usual divergingside edges 32. The blank 35 differs from the blank shown in Fig. 10 inhaving marginal notches or recesses 38 at the inner ends of thediverging side edges 32. Thus the diverging side edges 32 terminate inthe recesses 36 instead of joining the parallel side edges 3U. f

The recesses 35 are deep enough to meet, or at least come very close to,the longitudinal lines along which the metal is to be bent to form thetwo wedging side flanges of the finished spreader member. These bendlines are indicated by the dotted lines 3'! in Fig. 2. In other words,it is desirable that both ends of these lines of bend extend to theedges of the blank, and the recesses 35 are provided to bring the sideedges inward to the bend lines.

Fig, 3 shows the wedging side flanges 38 that are formed by bending thesheet metal upward along the dotted lines 3l. It is clearly apparentthat while the bending of the flanges 38 reduces the width of thewedging member at its leading end to less than the width of the bodyportion 2S, nevertheless no pinching action is involved in the reductionin width. The metal is bent upward along the lines 31 in a clean-cutmanner and without causing any strain on the metal between the twomarginal recesses 35.

While the particular blank configurations shown in Fig. 2 is practical,it does result in the formation of a distinct and somewhat abruptshoulder lill at the inner end of each side liange 33, as may be seen inFig. 4. It is desirable, therefore, to bevel the leading end of thecorresponding arm 2l of the Cotter pin 2l] to ride easily over theshoulder 40.

The preferred practice of my invention illustrated by Figs. 6, 7 and 8has the advantage of eliminating the shoulder G0, as will now be eX-plained. The blank, generally designated il in Fig. 6, has a bodyportion 42 with parallel side edges i3, and has an end enlargement 45with diverging side edges 4B. I-Iere again the blank configurationincludes marginal recesses il at the inner ends of the diverging sideedges 43. In this instance, however, the recesses il are formed in partsimply by extending the diverging side edges it well inside thelongitudinal zone defined by the parallel side edges 43. Bending theblank 4| as indicated by the two longitudinal dotted lines 48 results inthe formation of the two wedging side flanges 53 of Figs. '7 and 8. Fig,8 clearly brings out the fact that the described method of fabricationresults in smoothly functioning wedging surfaces, free of any abruptshoulder.

Fig. 9 illustrates a third practice of my invention wherein, strictlyspeaking, no recesses are employed. In this instance I make the bodyportion 5l of the spreader relatively narrow to accomplish the samepurpose as recesses, viz: to permit the previously described bend linesto extend at their opposite ends to the edge of the sheet metalmaterial. As is apparent in Fig. 9, the side edges 52 are spaced apartnot more than the distance between the side flanges 53. In this specificinstance the parallel side edges 52 are substantially equal to thespacing between the side flanges 53 so that the lines along which theblank is bent to form the side edges are substantially continuations ofthe parallel side edges 52.

The crux of the matter is that the side edges of the body portion of theblank extend inwardly,

at least inside the planes of the outer faces of the side flanges andpreferably at least to the planes defined by the inner faces of the sideanges. This relationship may be achieved either by cutting marginalrecesses in a blank having a body portion of conventional width, or maybe achieved by simply narrowing the width of the body portion,

It will be apparent to those skilled in the art that various changes andsubstitutions departing from the described constructions and proceduresmay be made within the scope of my appended claims.

I claim as my invention:

1. A spreader member for use in a cotter pin of the character described,comprising a sheet metal strip provided with laterally extendingprojections bent substantially at right angles to said strip to form twoside flanges at one end thereof of tapering configuration to serve asWedge means for the cotter pin, said strip having marginal recesses inits side edges at the inner ends of said iianges.

2. A spreader member for use in a cotter pin of the character described,comprising a sheet metal strip provided with laterally extendingprojections bent substantially at right angles to said strip to form twoside flanges at one end thereof of tapering configuration to serve aswedge means for the cotter pin, said strip having marginal recesses in-its side edges at the inner ends of said lianges, said recessesextending inward at least to the planes of the inner surfaces of saidfianges.

3. A spreader member for use in a cotter pin of the character described,comprising a sheet metal strip forming a flat longitudinal body providedwith laterally extending projections bent substantially at right anglesto said strip to form two side anges at one end thereof of taperingconfiguration to serve as wedge means for the cotter pin, the side edgesof said body at the inner ends of said iianges lying inside the planesof the outer faces of the flanges.

4. A spreader member for use in a cotter pin of the character described,comprising a sheet metal strip forming a at longitudinal body providedwith laterally extending projections bent substantially at right anglesto said strip to form two side flanges at one end thereof of taperingconfiguration to serve as wedge means for the cotter pin, the innerfaces of each of said side flanges extending from one edge of said stripto another edge of the strip.

5. A spreader member for use in a cotter pin of the character describedcomprising, a generally thin fiat strip of plastically deformablematerial provided with laterally extending projections bentsubstantially at right angles to said strip to form at least two sideanges adjacent one end thereof of tapering configuration to serve aswedge means for the cotter pin, said strip having marginal recesses inits side edges adjacent the inner ends of said flanges and extendingrespectively inward to substantially the bases of said iianges.

6. A spreader member for use in a cotter pin of the character describedcomprising, a strip of plastically deformable material provided withlaterally extending projections bent substantially at a right angle tosaid strip to form a side ange adjacent one end thereof of taperingconfiguration to serve as wedge means for the cotter pin, said striphaving a marginal recess in its side edge adjacent the inner endof saidfiange and extending inward to substantially the base of said flange.

SVEN J. STRID.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,925,804 Hiering Sept. 5, 19332,166,614 Strid July 18, 1939 2,386,887 Eckel Oct. 16, 1945 FOREIGNPATENTS Number Country Date 125,547 Great Britain Apr. 24, 1919

